But industry sources and venture capital researchers at analyst firm CB Insights questioned on Friday whether everything is as rosy as Maris is making it out to be.

One venture capitalist, who wished to remain anonymous, told Business Insider that Maris's departure is a "huge signal something was very wrong there".

"I haven’t heard any back story yet from my friends in [the] Valley but you have to think this was due to friction with Google execs," said the tech investor, before pointing to the closure of GV's dedicated European fund last year,. "He’s known for being abrasive and despite their rah rah culture it was without a doubt the 'Bill show' with everyone else in supporting roles. That’s why Wes Chan left, for example."

These are only rumours and, as you might expect, GV has previously denied the reported tensions between Maris and other GV employees.

Countering the rumours was Eze Vidra, a former partner at GV in Europe. He didn't have a negative word to say about Maris when Business Insider spoke to him on Friday, although it's unusual for a former Google employee to bad mouth the search giant.

GV is 1 of 3 Alphabet investment funds

GV was founded by Google in 2009 as Google Ventures. But the company no longer sits under Google. Today it falls under Alphabet — the parent company that Google created last year to separate its core search engine business from new ventures like GV, its secretive moonshot division, Project X, and home thermostat company, Nest.

Following Alphabet's formation, CEO Larry Page rebranded Google Ventures to GV to make it clear that the venture capital business was independent of Google.

GV is likely to say that there's no overlap between itself and the other Alphabet investment divisions but it's perfectly possible that they end up treading on one another's toes from time-to-time.

One startup cofounder even went as far as to say: "GV had no role after the Alphabet split."

Looking at the data

CB Insights looked at GV deal data over the last five years. The researchers found that GV made 46% less deals in 2015— the year that Alphabet was formed — than it did in 2014.

A chart showing how many deals GV has closed since 2011.CB Insights

The biggest drop-off in GV deal activity was at the seed stage, where GV went from a high of over 40 new deals in 2014 to 0 in the first half of 2016.

The CB Insights researchers wrote: "Growth investments done through Google Capital and direct minority investments by Google into the likes of SpaceX and Magic Leap have increased in the past two years."

Although GV is yet to make any seed stage deals in 2016, it has made several larger deals. In the first half of the year, GV made 31% more investments than the same period in 2015, but 30% fewer than in H1 2014, according to CB Insights.

A Google Ventures spokeswoman said: "Bill Maris has decided to step down to take a break with his family and tackle something new.

"David was instrumental in building GV into a 70+ person team with operations in Europe and the US, and over 300 investments. He led the fund’s investments in Uber and Nest. David has been with Google for nearly 17 years, starting as Google’s first communications director and taking the company through to IPO. Under his leadership, GV will continue to expand our mission to find and fund great entrepreneurs."